Carvey Company manufactures a variety of ballpoint pens. The company has just received an offer from an outside supplier to provide the ink cartridge for the company's pen line, at a price of $0.60 per dozen cartridges. The company is interested in this offer because its own production of cartridges is at capacity Carvey Company estimates that if the supplier's offer were accepted, the direct labor and variable manufacturing overhead costs of the pen line would be reduced by 10% and the direct materials cost would be reduced by 20%. Under present operations. Carvey Company manufactures all of its own pens from start to finish. The pens are sold through wholesalers at $4 per box. Each box contains one dozen pens. Foxed manufacturing overhead costs charged to the pen line total $30,000 each year. (The same equipment and facilities are used to produce several pen lines.) The present cost of producing one dozen pens (one box) is given below: Includes both variable and foxed manufacturing overhead, based on production of 100,000 boxes of pens each year. Due to the bankruptcy of a competitor Carvey Company expects to sell 150,000 boxes of pens next year. As previously stated, the company presently has enough capacity to produce the cartridges for only 100,000 boxes of pens annually. By incurring $39,000 in added fixed cost each year, the company could expand its production of cartridges to satisfy the anticipated demand for pens. The variable cost per unit to produce the additional cartridges would be the same as at present. a. Under these circumstances, how many boxes of cartridges should be purchased from the outside supplier and how many should be made by Carvey? b. Compute the total relevant cost for the following alternatives. (Do not round intermediate calculations. Round your total variable cost per box to 2 decimal places.)